Funding for this research was provided by:
Chinese University of Hong Kong (3230211)
Quality Education Fund (6904338)
Text and Data Mining valid from 2018-05-24
Received: 15 December 2017
Accepted: 2 May 2018
First Online: 24 May 2018
Ethics approval and consent to participate
: All of the procedures were approved by the institutional review board of the first author’s university, in compliance with the Declaration of Helsinki (Reference no. 14600817). We obtained parents’ informed consent prior to the study. The participants also gave their assent to participate in this study.
: The authors declare that they have no competing interests.
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